JPS6231549Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to a concrete panel used as a formwork when pouring concrete at a construction site or the like. This type of concrete panel is made of fluid concrete that is held in a predetermined mold during curing and is left under harsh natural conditions for a long time, and is also subjected to strong forces when released from the mold as it hardens. Because it is peeled off from hardened concrete, it usually causes severe damage after several applications, and becomes unfit for reuse. Furthermore, because the formwork is tightened with formwork tightening bolts that carry a considerable load each time, the exposed bolt insertion holes on the end face of the panel may crack or break before the panel itself, making it unusable as a concrete panel. many. In view of the above-mentioned circumstances, the purpose of this invention is to provide a concrete panel in which the bolt insertion holes are difficult to damage and the panel itself can withstand a considerable number of constructions. The present invention proposes a structure in which a high-hardness member is embedded and the entire surface is impregnated with a thermosetting resin. The following description will be made based on the accompanying drawings. In FIGS. 1 and 2, a thin plate-like member 2 having a higher hardness than the wooden board 1 is embedded around the periphery of the bolt insertion hole 1a on the surface of the wooden board 1, and the surface of the board 1 is impregnated with a thermosetting resin 3. Adhered concrete panels are shown. As the wood board material 1, plywood, insulation board, fiber board, particle board, etc. are used. As the high-hardness member 2, a metal member such as aluminum stainless steel or tin, or a synthetic resin member such as FRP or melamine hardened resin, which has a higher hardness than the wood board 1, is used in a thin plate shape and has a peripheral edge shape of the through hole 1a.
Further, as shown in the third figure, there is a hollow hanging part 2 below it.
It is more effective to use a material formed with a. Examples of the thermosetting resin 3 include epoxy, polypropylene, polyester, furan, etc., and the surface of the wood board 1 can be coated with it by coating with a roll coater or the like or by placing a sheet-shaped molded product.

[Table] When the above-mentioned product was actually used during concrete construction, the bolt insertion hole and the panel itself were damaged in just one use with the comparative example, and the panel itself became unusable, whereas the example with the comparative example was unusable. Even after continuous use for 20 times, there were no cracks near the bolt insertion holes or damage to the panel itself, and the panel was in good condition to withstand reuse. Although almost similar results were obtained with thermosetting resins other than epoxy resins, it is difficult to correct panel warping due to volumetric shrinkage during thermosetting,
It takes a long time (2 weeks to 1 week) to exhibit stable physical properties.
It is most preferable to use an epoxy resin because it requires several months of use, and furthermore, the resin surface is eroded by the strong alkalinity of concrete, resulting in a decrease in the number of repeated uses. As described above, according to the concrete panel according to the present invention, the physical properties necessary for the concrete panel are improved by the hardened film and impregnated layer of thermosetting resin, and the bolt insertion holes are protected by a high hardness material. This makes it possible to use it repeatedly a considerable number of times.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a concrete panel according to the present invention, FIG. 2 is a cross-sectional perspective view taken along the line A-A in FIG. FIG. 4 is an explanatory diagram of the state of the heat pressing process. 1...Wood board material, 1a...Through hole for bolt insertion,
2... High hardness thin plate member, 2a... Hollow hanging part, 3... Thermosetting resin.

Claims (1)

[Scope of claim for utility model registration] (1) On the periphery of the through hole for bolt insertion on the surface of the wooden board,
A thin plate-like member with higher hardness than the plate material is arranged, the surface of the plate material is coated with a thermosetting resin and heat-pressed together, and the high-hardness thin plate-like member is buried in the periphery of the through-hole for bolt insertion. Also, a concrete panel comprising the thermosetting resin impregnated into the surface layer of the board. (2) The concrete panel according to claim 1, wherein the thin plate member has a hollow hanging portion.